With the development of mobile terminal technology, there are more and more people using mobile terminals, and there are higher and higher requirements put forward on the mobile terminal encryption technology, for example, the following situation may be encountered when using a terminal: the user cannot take the terminal with himself or herself anytime and anywhere, especially when the terminal is a relatively large tablet, and when the user leaves the terminal, the terminal may be lost or the private data may be leaked out, or the terminal stores data or files which we do not want others to look at, therefore the user may need to encrypt the terminal, particularly encrypt the hardware, and the subscriber identity card (such as SIM card, USIM card and so on) is the hardware device essential for each terminal whose card can be separated, and for the terminal, the subscriber identity card can be easily plugged in and plugged out, and the plug-in and plug-out of the subscriber identity card is very easy especially for the tablet. However, currently there exists no technology to encrypt the terminal with the subscriber identity card in the related art.